The present invention relates generally to fluid supply systems for delivering various fluids to target objects such as workpieces. More particularly, the invention relates to program-controlled, and programmable systems, for delivering metered quantities of fluid such as lubricants to workpieces or workstock in manufacturing or other industrial operations.
Various industrial processes involve advancing a continuous supply of material (generically, a xe2x80x9cworkpiecexe2x80x9d) which is processed in various ways to produce a finished product. Throughout various stages of manufacture, the workpiece often requires the application of fluids, e.g., lubricants, or coolants. Existing fluid supply systems have included die lubricant applicators for distributing lubricants from a pressurized source of lubricant in an automated or programmed manner, using various types of control means. For example, some such known systems (e.g., U.S. Pat. Nos. 3,619,709 and 5,205,378) deliver lubricant to one or more injector nozzles on a die press or the like by using fluid pressure or the like as the primary control parameter. The first-mentioned such system, as well as others, utilized solenoid operated valves for selectively gating the flow of lubricant to the injector nozzles at the die press. Other such systems (e.g., U.S. Pat. No. 5,531,085) use a programmable logic controller that cause the solenoid valves to be actuated for a period responsive to the movement of the die press. In this manner, the systems can (at least theoretically) pass a predetermined volume of lubricant from a pressurized source of lubricant to the injector nozzles at predetermined times. Systems of this latter type may also include a programmable counter capable of inhibiting the opening of a valve for given number of die-press cycles.
Other prior art devices have implemented liquid dispensers for sheet stock or other substantially flat workpieces. A good example of one such prior art device of this type is disclosed in U.S. Pat. No. 5,797,983 titled xe2x80x9cCONTACT LUBRICATOR WITH METERED SUPPLY,xe2x80x9d assigned to the Assignee of the present invention. This device includes a pair of hollow elongated rollers which contact the advancing workpiece and apply liquid lubricant to the workpiece as it passes between the rollers. In this device, a liquid-dispensing apparatus meters a predetermined quantity of the liquid to the rollers, for application to the workpiece by coupling a liquid source to a dispensing tube disposed within and extending axially along the inside of the hollow elongated rollers. The dispensing tube within the rollers has a closed end which causes the liquid to be expelled as a spray in metered quantities through a series of spaced apertures in the dispensing tube. The hollow elongated roller is covered by a resiliently compressible liquid-transmissible outer cover. The sprayed liquid passes through a perforated wall of the roller and is absorbed by the resiliently compressible liquid-transmissible outer cover. In a typical implementation, the apparatus includes oppositely disposed rollers which contact the workpiece from opposite sides to apply liquid to both sides of the workpiece.
In the above-described device, the movement of the workpiece across the rollers causes the rollers to rotate, which in turn causes a pump to reciprocate. The reciprocation of the pump results in metered quantities of fluid being supplied to the rollers. In this embodiment, the pump was directly adjacent to one of the rollers. A rotary cam supplied on an end cap of the roller actuated a piston of the pump. Devices of this nature have been utilized in various metal working operations, such as punching, stamping, blanking, wall-forming, etc.
In its major aspects the present invention is directed to a fluid supply system that provides fluid to a workpiece. The fluid supply system includes a processor, a memory subsystem and fluid application code. The memory subsystem is coupled to the processor and stores data and instructions for the processor. The fluid application code causes the processor to perform the steps of receiving a workpiece width, a workpiece feed length, a workpiece stroke rate, a workpiece fluid thickness and a calibrated flow rate. The fluid application code then controls the processor to cause fluid to be periodically provided to the workpiece for a fixed duration as a function of the received workpiece width, workpiece feed length, workpiece stroke rate, workpiece fluid thickness and the calibrated flow rate.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.